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-              r497ae7b
+              rae75080a
 /*
+  Default header file for malloc-2.8.x, written by Doug Lea
+  and released to the public domain, as explained at
+  http://creativecommons.org/licenses/publicdomain.
+  last update: Mon Aug 15 08:55:52 2005  Doug Lea  (dl at gee)
+ * Copyright (c) 2009 Martin Decky
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * - Redistributions of source code must retain the above copyright
+ *   notice, this list of conditions and the following disclaimer.
+ * - Redistributions in binary form must reproduce the above copyright
+ *   notice, this list of conditions and the following disclaimer in the
+ *   documentation and/or other materials provided with the distribution.
+ * - The name of the author may not be used to endorse or promote products
+ *   derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+  This header is for ANSI C/C++ only.  You can set any of
+  the following #defines before including:
+/** @addtogroup libc
+ * @{
+ */
+/** @file
+ */
+  * If USE_DL_PREFIX is defined, it is assumed that malloc.c
+    was also compiled with this option, so all routines
+    have names starting with "dl".
+#ifndef LIBC_MALLOC_H_
+#define LIBC_MALLOC_H_
+  * If HAVE_USR_INCLUDE_MALLOC_H is defined, it is assumed that this
+    file will be #included AFTER <malloc.h>. This is needed only if
+    your system defines a struct mallinfo that is incompatible with the
+    standard one declared here.  Otherwise, you can include this file
+    INSTEAD of your system system <malloc.h>.  At least on ANSI, all
+    declarations should be compatible with system versions
+#include <sys/types.h>
+  * If MSPACES is defined, declarations for mspace versions are included.
+*/
+extern void __heap_init(void);
+extern uintptr_t get_max_heap_addr(void);
+#ifndef MALLOC_280_H
+#define MALLOC_280_H
+extern void *malloc(const size_t size);
+extern void *memalign(const size_t align, const size_t size);
+extern void *realloc(const void *addr, const size_t size);
+extern void free(const void *addr);
-#ifdef __cplusplus
-extern "C" {
 #endif
+#include <stddef.h>   /* for size_t */
+#if !ONLY_MSPACES
+#ifndef USE_DL_PREFIX
+#define dlcalloc               calloc
+#define dlfree                 free
+#define dlmalloc               malloc
+#define dlmemalign             memalign
+#define dlrealloc              realloc
+#define dlvalloc               valloc
+#define dlpvalloc              pvalloc
+#define dlmallinfo             mallinfo
+#define dlmallopt              mallopt
+#define dlmalloc_trim          malloc_trim
+#define dlmalloc_stats         malloc_stats
+#define dlmalloc_usable_size   malloc_usable_size
+#define dlmalloc_footprint     malloc_footprint
+#define dlmalloc_max_footprint malloc_max_footprint
+#define dlindependent_calloc   independent_calloc
+#define dlindependent_comalloc independent_comalloc
+#endif /* USE_DL_PREFIX */
+/*
+  malloc(size_t n)
+  Returns a pointer to a newly allocated chunk of at least n bytes, or
+  null if no space is available, in which case errno is set to ENOMEM
+  on ANSI C systems.
+  If n is zero, malloc returns a minimum-sized chunk. (The minimum
+  size is 16 bytes on most 32bit systems, and 32 bytes on 64bit
+  systems.)  Note that size_t is an unsigned type, so calls with
+  arguments that would be negative if signed are interpreted as
+  requests for huge amounts of space, which will often fail. The
+  maximum supported value of n differs across systems, but is in all
+  cases less than the maximum representable value of a size_t.
+*/
+void* dlmalloc(size_t);
+/*
+  free(void* p)
+  Releases the chunk of memory pointed to by p, that had been previously
+  allocated using malloc or a related routine such as realloc.
+  It has no effect if p is null. If p was not malloced or already
+  freed, free(p) will by default cuase the current program to abort.
+*/
+void  dlfree(void*);
+/*
+  calloc(size_t n_elements, size_t element_size);
+  Returns a pointer to n_elements * element_size bytes, with all locations
+  set to zero.
+*/
+void* dlcalloc(size_t, size_t);
+/*
+  realloc(void* p, size_t n)
+  Returns a pointer to a chunk of size n that contains the same data
+  as does chunk p up to the minimum of (n, p's size) bytes, or null
+  if no space is available.
+  The returned pointer may or may not be the same as p. The algorithm
+  prefers extending p in most cases when possible, otherwise it
+  employs the equivalent of a malloc-copy-free sequence.
+  If p is null, realloc is equivalent to malloc.
+  If space is not available, realloc returns null, errno is set (if on
+  ANSI) and p is NOT freed.
+  if n is for fewer bytes than already held by p, the newly unused
+  space is lopped off and freed if possible.  realloc with a size
+  argument of zero (re)allocates a minimum-sized chunk.
+  The old unix realloc convention of allowing the last-free'd chunk
+  to be used as an argument to realloc is not supported.
+*/
+void* dlrealloc(void*, size_t);
+/*
+  memalign(size_t alignment, size_t n);
+  Returns a pointer to a newly allocated chunk of n bytes, aligned
+  in accord with the alignment argument.
+  The alignment argument should be a power of two. If the argument is
+  not a power of two, the nearest greater power is used.
+-byte alignment is guaranteed by normal malloc calls, so don't
+  bother calling memalign with an argument of 8 or less.
+  Overreliance on memalign is a sure way to fragment space.
+*/
+void* dlmemalign(size_t, size_t);
+/*
+  valloc(size_t n);
+  Equivalent to memalign(pagesize, n), where pagesize is the page
+  size of the system. If the pagesize is unknown, 4096 is used.
+*/
+void* dlvalloc(size_t);
+/*
+  mallopt(int parameter_number, int parameter_value)
+  Sets tunable parameters The format is to provide a
+  (parameter-number, parameter-value) pair.  mallopt then sets the
+  corresponding parameter to the argument value if it can (i.e., so
+  long as the value is meaningful), and returns 1 if successful else
+.  SVID/XPG/ANSI defines four standard param numbers for mallopt,
+  normally defined in malloc.h.  None of these are use in this malloc,
+  so setting them has no effect. But this malloc also supports other
+  options in mallopt:
+  Symbol            param #  default    allowed param values
+  M_TRIM_THRESHOLD     -1   2*1024*1024   any   (-1U disables trimming)
+  M_GRANULARITY        -2     page size   any power of 2 >= page size
+  M_MMAP_THRESHOLD     -3      256*1024   any   (or 0 if no MMAP support)
+*/
+int dlmallopt(int, int);
+#define M_TRIM_THRESHOLD     (-1)
+#define M_GRANULARITY        (-2)
+#define M_MMAP_THRESHOLD     (-3)
+/*
+  malloc_footprint();
+  Returns the number of bytes obtained from the system.  The total
+  number of bytes allocated by malloc, realloc etc., is less than this
+  value. Unlike mallinfo, this function returns only a precomputed
+  result, so can be called frequently to monitor memory consumption.
+  Even if locks are otherwise defined, this function does not use them,
+  so results might not be up to date.
+*/
+size_t dlmalloc_footprint(void);
+size_t dlmalloc_max_footprint(void);
+#if !NO_MALLINFO
+/*
+  mallinfo()
+  Returns (by copy) a struct containing various summary statistics:
+  arena:     current total non-mmapped bytes allocated from system
+  ordblks:   the number of free chunks
+  smblks:    always zero.
+  hblks:     current number of mmapped regions
+  hblkhd:    total bytes held in mmapped regions
+  usmblks:   the maximum total allocated space. This will be greater
+                than current total if trimming has occurred.
+  fsmblks:   always zero
+  uordblks:  current total allocated space (normal or mmapped)
+  fordblks:  total free space
+  keepcost:  the maximum number of bytes that could ideally be released
+               back to system via malloc_trim. ("ideally" means that
+               it ignores page restrictions etc.)
+  Because these fields are ints, but internal bookkeeping may
+  be kept as longs, the reported values may wrap around zero and
+  thus be inaccurate.
+*/
+#ifndef HAVE_USR_INCLUDE_MALLOC_H
+#ifndef _MALLOC_H
+#ifndef MALLINFO_FIELD_TYPE
+#define MALLINFO_FIELD_TYPE size_t
+#endif /* MALLINFO_FIELD_TYPE */
+struct mallinfo {
+  MALLINFO_FIELD_TYPE arena;    /* non-mmapped space allocated from system */
+  MALLINFO_FIELD_TYPE ordblks;  /* number of free chunks */
+  MALLINFO_FIELD_TYPE smblks;   /* always 0 */
+  MALLINFO_FIELD_TYPE hblks;    /* always 0 */
+  MALLINFO_FIELD_TYPE hblkhd;   /* space in mmapped regions */
+  MALLINFO_FIELD_TYPE usmblks;  /* maximum total allocated space */
+  MALLINFO_FIELD_TYPE fsmblks;  /* always 0 */
+  MALLINFO_FIELD_TYPE uordblks; /* total allocated space */
+  MALLINFO_FIELD_TYPE fordblks; /* total free space */
+  MALLINFO_FIELD_TYPE keepcost; /* releasable (via malloc_trim) space */
+};
+#endif  /* _MALLOC_H */
+#endif  /* HAVE_USR_INCLUDE_MALLOC_H */
+struct mallinfo dlmallinfo(void);
+#endif  /* NO_MALLINFO */
+/*
+  independent_calloc(size_t n_elements, size_t element_size, void* chunks[]);
+  independent_calloc is similar to calloc, but instead of returning a
+  single cleared space, it returns an array of pointers to n_elements
+  independent elements that can hold contents of size elem_size, each
+  of which starts out cleared, and can be independently freed,
+  realloc'ed etc. The elements are guaranteed to be adjacently
+  allocated (this is not guaranteed to occur with multiple callocs or
+  mallocs), which may also improve cache locality in some
+  applications.
+  The "chunks" argument is optional (i.e., may be null, which is
+  probably the most typical usage). If it is null, the returned array
+  is itself dynamically allocated and should also be freed when it is
+  no longer needed. Otherwise, the chunks array must be of at least
+  n_elements in length. It is filled in with the pointers to the
+  chunks.
+  In either case, independent_calloc returns this pointer array, or
+  null if the allocation failed.  If n_elements is zero and "chunks"
+  is null, it returns a chunk representing an array with zero elements
+  (which should be freed if not wanted).
+  Each element must be individually freed when it is no longer
+  needed. If you'd like to instead be able to free all at once, you
+  should instead use regular calloc and assign pointers into this
+  space to represent elements.  (In this case though, you cannot
+  independently free elements.)
+  independent_calloc simplifies and speeds up implementations of many
+  kinds of pools.  It may also be useful when constructing large data
+  structures that initially have a fixed number of fixed-sized nodes,
+  but the number is not known at compile time, and some of the nodes
+  may later need to be freed. For example:
+  struct Node { int item; struct Node* next; };
+  struct Node* build_list() {
+    struct Node** pool;
+    int n = read_number_of_nodes_needed();
+    if (n <= 0) return 0;
+    pool = (struct Node**)(independent_calloc(n, sizeof(struct Node), 0);
+    if (pool == 0) die();
+    // organize into a linked list...
+    struct Node* first = pool[0];
+    for (i = 0; i < n-1; ++i)
+      pool[i]->next = pool[i+1];
+    free(pool);     // Can now free the array (or not, if it is needed later)
+    return first;
+  }
+*/
+void** dlindependent_calloc(size_t, size_t, void**);
+/*
+  independent_comalloc(size_t n_elements, size_t sizes[], void* chunks[]);
+  independent_comalloc allocates, all at once, a set of n_elements
+  chunks with sizes indicated in the "sizes" array.    It returns
+  an array of pointers to these elements, each of which can be
+  independently freed, realloc'ed etc. The elements are guaranteed to
+  be adjacently allocated (this is not guaranteed to occur with
+  multiple callocs or mallocs), which may also improve cache locality
+  in some applications.
+  The "chunks" argument is optional (i.e., may be null). If it is null
+  the returned array is itself dynamically allocated and should also
+  be freed when it is no longer needed. Otherwise, the chunks array
+  must be of at least n_elements in length. It is filled in with the
+  pointers to the chunks.
+  In either case, independent_comalloc returns this pointer array, or
+  null if the allocation failed.  If n_elements is zero and chunks is
+  null, it returns a chunk representing an array with zero elements
+  (which should be freed if not wanted).
+  Each element must be individually freed when it is no longer
+  needed. If you'd like to instead be able to free all at once, you
+  should instead use a single regular malloc, and assign pointers at
+  particular offsets in the aggregate space. (In this case though, you
+  cannot independently free elements.)
+  independent_comallac differs from independent_calloc in that each
+  element may have a different size, and also that it does not
+  automatically clear elements.
+  independent_comalloc can be used to speed up allocation in cases
+  where several structs or objects must always be allocated at the
+  same time.  For example:
+  struct Head { ... }
+  struct Foot { ... }
+  void send_message(char* msg) {
+    int msglen = strlen(msg);
+    size_t sizes[3] = { sizeof(struct Head), msglen, sizeof(struct Foot) };
+    void* chunks[3];
+    if (independent_comalloc(3, sizes, chunks) == 0)
+      die();
+    struct Head* head = (struct Head*)(chunks[0]);
+    char*        body = (char*)(chunks[1]);
+    struct Foot* foot = (struct Foot*)(chunks[2]);
+    // ...
+  }
+  In general though, independent_comalloc is worth using only for
+  larger values of n_elements. For small values, you probably won't
+  detect enough difference from series of malloc calls to bother.
+  Overuse of independent_comalloc can increase overall memory usage,
+  since it cannot reuse existing noncontiguous small chunks that
+  might be available for some of the elements.
+*/
+void** dlindependent_comalloc(size_t, size_t*, void**);
+/*
+  pvalloc(size_t n);
+  Equivalent to valloc(minimum-page-that-holds(n)), that is,
+  round up n to nearest pagesize.
+/** @}
  */
-void*  dlpvalloc(size_t);
-/*
-  malloc_trim(size_t pad);
-  If possible, gives memory back to the system (via negative arguments
-  to sbrk) if there is unused memory at the `high' end of the malloc
-  pool or in unused MMAP segments. You can call this after freeing
-  large blocks of memory to potentially reduce the system-level memory
-  requirements of a program. However, it cannot guarantee to reduce
-  memory. Under some allocation patterns, some large free blocks of
-  memory will be locked between two used chunks, so they cannot be
-  given back to the system.
-  The `pad' argument to malloc_trim represents the amount of free
-  trailing space to leave untrimmed. If this argument is zero, only
-  the minimum amount of memory to maintain internal data structures
-  will be left. Non-zero arguments can be supplied to maintain enough
-  trailing space to service future expected allocations without having
-  to re-obtain memory from the system.
-  Malloc_trim returns 1 if it actually released any memory, else 0.
-*/
-int  dlmalloc_trim(size_t);
-/*
-  malloc_usable_size(void* p);
-  Returns the number of bytes you can actually use in
-  an allocated chunk, which may be more than you requested (although
-  often not) due to alignment and minimum size constraints.
-  You can use this many bytes without worrying about
-  overwriting other allocated objects. This is not a particularly great
-  programming practice. malloc_usable_size can be more useful in
-  debugging and assertions, for example:
-  p = malloc(n);
-  assert(malloc_usable_size(p) >= 256);
-*/
-size_t dlmalloc_usable_size(void*);
-/*
-  malloc_stats();
-  Prints on stderr the amount of space obtained from the system (both
-  via sbrk and mmap), the maximum amount (which may be more than
-  current if malloc_trim and/or munmap got called), and the current
-  number of bytes allocated via malloc (or realloc, etc) but not yet
-  freed. Note that this is the number of bytes allocated, not the
-  number requested. It will be larger than the number requested
-  because of alignment and bookkeeping overhead. Because it includes
-  alignment wastage as being in use, this figure may be greater than
-  zero even when no user-level chunks are allocated.
-  The reported current and maximum system memory can be inaccurate if
-  a program makes other calls to system memory allocation functions
-  (normally sbrk) outside of malloc.
-  malloc_stats prints only the most commonly interesting statistics.
-  More information can be obtained by calling mallinfo.
-*/
-void  dlmalloc_stats(void);
-#endif /* !ONLY_MSPACES */
-#if MSPACES
-/*
-  mspace is an opaque type representing an independent
-  region of space that supports mspace_malloc, etc.
-*/
-typedef void* mspace;
-/*
-  create_mspace creates and returns a new independent space with the
-  given initial capacity, or, if 0, the default granularity size.  It
-  returns null if there is no system memory available to create the
-  space.  If argument locked is non-zero, the space uses a separate
-  lock to control access. The capacity of the space will grow
-  dynamically as needed to service mspace_malloc requests.  You can
-  control the sizes of incremental increases of this space by
-  compiling with a different DEFAULT_GRANULARITY or dynamically
-  setting with mallopt(M_GRANULARITY, value).
-*/
-mspace create_mspace(size_t capacity, int locked);
-/*
-  destroy_mspace destroys the given space, and attempts to return all
-  of its memory back to the system, returning the total number of
-  bytes freed. After destruction, the results of access to all memory
-  used by the space become undefined.
-*/
-size_t destroy_mspace(mspace msp);
-/*
-  create_mspace_with_base uses the memory supplied as the initial base
-  of a new mspace. Part (less than 128*sizeof(size_t) bytes) of this
-  space is used for bookkeeping, so the capacity must be at least this
-  large. (Otherwise 0 is returned.) When this initial space is
-  exhausted, additional memory will be obtained from the system.
-  Destroying this space will deallocate all additionally allocated
-  space (if possible) but not the initial base.
-*/
-mspace create_mspace_with_base(void* base, size_t capacity, int locked);
-/*
-  mspace_malloc behaves as malloc, but operates within
-  the given space.
-*/
-void* mspace_malloc(mspace msp, size_t bytes);
-/*
-  mspace_free behaves as free, but operates within
-  the given space.
-  If compiled with FOOTERS==1, mspace_free is not actually needed.
-  free may be called instead of mspace_free because freed chunks from
-  any space are handled by their originating spaces.
-*/
-void mspace_free(mspace msp, void* mem);
-/*
-  mspace_realloc behaves as realloc, but operates within
-  the given space.
-  If compiled with FOOTERS==1, mspace_realloc is not actually
-  needed.  realloc may be called instead of mspace_realloc because
-  realloced chunks from any space are handled by their originating
-  spaces.
-*/
-void* mspace_realloc(mspace msp, void* mem, size_t newsize);
-/*
-  mspace_calloc behaves as calloc, but operates within
-  the given space.
-*/
-void* mspace_calloc(mspace msp, size_t n_elements, size_t elem_size);
-/*
-  mspace_memalign behaves as memalign, but operates within
-  the given space.
-*/
-void* mspace_memalign(mspace msp, size_t alignment, size_t bytes);
-/*
-  mspace_independent_calloc behaves as independent_calloc, but
-  operates within the given space.
-*/
-void** mspace_independent_calloc(mspace msp, size_t n_elements,
-                                 size_t elem_size, void* chunks[]);
-/*
-  mspace_independent_comalloc behaves as independent_comalloc, but
-  operates within the given space.
-*/
-void** mspace_independent_comalloc(mspace msp, size_t n_elements,
-                                   size_t sizes[], void* chunks[]);
-/*
-  mspace_footprint() returns the number of bytes obtained from the
-  system for this space.
-*/
-size_t mspace_footprint(mspace msp);
-#if !NO_MALLINFO
-/*
-  mspace_mallinfo behaves as mallinfo, but reports properties of
-  the given space.
-*/
-struct mallinfo mspace_mallinfo(mspace msp);
-#endif /* NO_MALLINFO */
-/*
-  mspace_malloc_stats behaves as malloc_stats, but reports
-  properties of the given space.
-*/
-void mspace_malloc_stats(mspace msp);
-/*
-  mspace_trim behaves as malloc_trim, but
-  operates within the given space.
-*/
-int mspace_trim(mspace msp, size_t pad);
-/*
-  An alias for mallopt.
-*/
-int mspace_mallopt(int, int);
-#endif  /* MSPACES */
-#ifdef __cplusplus
-};  /* end of extern "C" */
-#endif
-#endif /* MALLOC_280_H */
- /** @}
- */

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